I have an Android Nexus tablet with only wifi. When flying I have no wifi connection. If I generate a route on a PC then save to cloud I can load it onto the device while in wifi range eg at home. However I cannot save it onto the device locally for use later when I have no connection. 

Route  - Save As - brings up  a box with a name suggestion but when I save the box dissappears very fast and when I try to open it from the same menu there are no routes saved.

I am on Andoid 6

Am I doing something wrong ?
Regards
Nick